dmaengine: at_hdmac: Add support for memory to memory sg transfers
dmaengine: at_hdmac: Add support for memory to memory sg transfers

This patch adds support for memory to memory scatter-gather transfers.

Changes from V1:
   * Fixed coding style of the multi-line comments.

Changes from V2:
   * Added setup of 'desc->tx_width' that is needed to calculate the
     residue.

Signed-off-by: Torsten Fleischer <29f2503de73ca86bc6141e3a582ce370460f04bb@gmail.com>
Acked-by: Nicolas Ferre <45b517be0e5ec6dc3a39715767c1d18e090d39b4@atmel.com>
Signed-off-by: Vinod Koul <5cf69c63beb17bf38d63aa0e923ee8256af0e205@intel.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs